Chrontel 7306 is an SDVO ADD2 card that plugs in PCIe and receives
SDVO signals from mainboards integrated in Intel SDVO chipsets like
945G/965G and also transfer SDVO signal to digital signals for LCD
panels.

and Wikipedia:

Wikipedia: Serial Digital Video Out is a proprietary Intel technology
introduced with their 9xx-series of motherboard chipsets. SDVO makes
it possible to use a 16-line PCIe slot add additional video signalling
interfaces such as VGA and DVI monitor outputs, SDTV and HDTV
television outputs, or TV tuner inputs to a system board containing an
integrated Intel 9xx-series graphics processor. SDVO adapters are
variously designated as ADD2 (advanced digital display, 2nd
generation)